Internal combustion engine utilize intake systems to provide intake air to cylinders in the engine. Improved mixing of the intake air with fuel in the cylinder may be desirable to enable an increase in engine efficiency and decreased engine emissions. Specifically, turbulent flow of the intake air may be generated to improve mixing in the cylinders in the engine. However, generating turbulence in the intake system increases losses in the intake system, decreasing engine efficiency and subverting the aforementioned objective of increased efficiency. Engine packaging constraints may also affect the generation of a flow pattern for improved mixing the intake air and fuel in the cylinder.
As such in one approach to overcome at least some of the aforementioned problems, an intake system for an internal combustion engine is provided. The intake system may include an intake manifold fluidly connected to a cylinder, an intake valve coupled to the cylinder having an air supply duct longitudinally extending through a portion of a valve stem and having an outlet opening into the intake manifold and an inlet fluidly connected to a supply line fluidly connected to an intake passage downstream of a compressor and upstream of a throttle, and a shut-off valve positioned in the supply line configured to adjust the flow of gas through the supply line. In this way, intake air is flowed through the valve stem which mixes with air flowing through the intake manifold to generate turbulence (e.g., swirling) in the intake air flow immediately before the air enters the cylinders. As a result, combustion efficiency is increased and engine emissions are reduce while losses in the intake system are not significantly increased due to the location convergence of the intake air streams which is adjacent to the intake opening of the cylinder.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. Additionally, the above issues have been recognized by the inventors herein, and are not admitted to be known.